The present invention relates to UV-light-absorbing quaternary polysiloxanes, to processes for the preparation thereof and to the use of such UV-light-absorbing quaternary polysiloxanes in formulations for textile care and cosmetic preparations.
It is well-known that UV (ultra-violet) light having wavelengths from 200 to 400 nm is responsible for the bleaching and the damage of textiles, synthetic fibers and natural fibers (e.g., wool, cotton and hair).
For this reason, there is a growing need for compounds which shield textiles, synthetic fibers and natural fibers from UV radiation, or permit control over the degree of damage caused by UV light.
It is therefore desirable to provide compounds which can exert control over the UV radiation to which the textiles or the synthetic or natural fibers are exposed.
The literature discloses a large number of compounds which are used for UV light protection of fibers, dyes and pigments. Such compounds are typically used directly in the preparation of the fibers.
However, these compounds do not have a caring or softening effect. In addition, the prior art compounds often lack adhesion to the surface of the fiber, which means that after just a few wash operations, the UV protection on the fibers is lost.
It is therefore desirable to provide compounds which are capable of: (i) exerting a care effect on natural or synthetic fibers, (ii) exhibiting high substantivity, i.e., high affinity, to the fibers resulting in an improved permanency, and (iii) offering protection against damage by mechanical and/or optical (e.g., UV light) effects. The term xe2x80x98care effectxe2x80x99 is used herein to denote a softening and/or conditioning effect, possibly in combination with a reduction in fiber damage after mechanical stress. Moreover, and in some embodiments, the term xe2x80x98care effectxe2x80x99 denotes an anti-wrinkle effect (easy ironing effect), improved elasticity and improved tear strength of the fabric.
In order to be able to provide adequate UV protection even after a number of washes, the compounds should also be able to be incorporated into fabric softener formulations and attach to the fibers during the fabric softener cycle.
Quaternary polysiloxanes are likewise known from the literature and are described, for example, in EP-A-0 282 720 and DE-A-37 19 086. Such compounds are known, in particular, for their conditioning properties in hair cosmetics and for their softening and care effects in textile treatment. Compounds of this type are also used in order to increase the elasticity and the tear strength of textiles and to reduce the formation of folds or creases thereof and/or to facilitate ironing later on (xe2x80x9ceasy ironingxe2x80x9d) (see, for example, WO-01/25385, WO-01/25382, WO-01/25381, WO-01/25380, WO-99/55953). Compounds as described in EP-282 720 and DE-37 19 086, however, do not exhibit protection against the harmful effect of UV radiation.
A disadvantage according to the prior art is therefore that in each case special compounds have to be provided in order to achieve the effects described above.
An object of the present invention is to provide compounds that can be used universally, which exert a smoothing, care and softening effect on natural or synthetic fibers, exhibit high affinity to the natural or synthetic fibers (e.g., wool, cotton or hair) or other surfaces (e.g., skin), and reduce damage by mechanical and/or optical effects (e.g., UV light).
Surprisingly, it was found that the abovementioned object is achieved by UV-light-absorbing quaternary polysiloxanes.
The present invention therefore provides UV-light-absorbing quaternary polysiloxanes of general formula (I) 
in which radicals
R1 are identical or different and are in each case lower alkyl radicals having 1 to 4 carbon atoms or phenyl radicals,
R2 is R1 or a radical of formula (Ia)
R2=-M-Z+ Axe2x88x92xe2x80x83xe2x80x83(Ia) 
xe2x80x83with the proviso that in the average molecule at least one radical R2 is a radical of the formula -M-Z+ Axe2x88x92,
xe2x80x83wherein
xe2x80x83Z is a radical of formula (Ib) 
R3, R4 are alkyl radicals having 1 to 22 carbon atoms or alkenyl radicals having 2 to 22 carbon atoms, in which the alkyl or alkenyl radicals can include hydroxyl groups,
R5 is a monovalent chromophore radical responsible for UV-absorption of formula (Ic) 
xe2x80x83in which
R6 is 
R7 is xe2x80x94CHxe2x95x90CHxe2x80x94,
R8 are identical or different and in each case are hydrogen, alkyl, haloalkyl, halogen, phenyl, hydroxyl, alkoxy, amino, alkylamino, dialkylamino, di(hydroxyalkyl)amino or di(polyalkoxy)amino radicals,
m=0 or 1,
n=0 or 1,
o=0 to 5,
x=0 to 6,
M is a divalent hydrocarbon radical having at least 4 carbon atoms which has one hydroxyl group and which may be interrupted by one or more oxygen atoms, where the N atom of the radical Z is bonded to the radical M via the carbon atom adjacent to the Cxe2x80x94OH group in the radical M,
Axe2x88x92 is an inorganic or organic anion which stems from a customary physiologically compatible acid HA,
a, independently of the others, has a value from 1 to 200, and b has a value from 0 to 10.
The present invention further provides for the preparation of the compounds of formula (I) mentioned-above. The process according to the present invention comprises reacting compounds of general formula (II) 
in which the radicals
R1 are identical or different and in each case are lower alkyl radicals having 1 to 4 carbon atoms or phenyl radicals,
R9 is R1 or a monovalent radical which corresponds to the structure of the radical M, where the radical R9 has an epoxide group in place of the linkage to Z and the hydroxyl group,
xe2x80x83with the proviso that, in the average molecule, at least one radical R9 is a monovalent radical which corresponds to the structure of the radical M, where the radical R9 has an epoxide group in place of the linkage to Z and the hydroxyl group,
a independently of the others, has a value from 1 to 200 and
b has a value from 0 to 10,
with tertiary amines of general formula (IIb) 
xe2x80x83wherein
R3, R4 are alkyl radicals having 1 to 22 carbon atoms or alkenyl radicals having 2 to 22 carbon atoms, in which the alkyl or alkenyl radicals can include hydroxyl groups,
R5 is a monovalent chromophore radical responsible for the UV-absorption of formula (Ic) 
xe2x80x83in which
R6 is 
R7 is xe2x80x94CHxe2x95x90CHxe2x80x94,
R8 are identical or different and are in each case hydrogen, alkyl, haloalkyl, halogen, phenyl, hydroxyl, alkoxy, amino, alkylamino, dialkylamino, di(hydroxyalkyl)amino or di(polyalkoxy)amino radicals,
m=0 or 1,
n=0 or 1,
o=0 to 5, and
x=0 to 6,
in a manner known per se. Specifically, the reacting step is performed using quantitative ratios such that each epoxide group corresponds to at least one tertiary amino group. Moreover, the reacting step is carried out in the presence of a customary physiologically compatible organic or inorganic acid equivalent HA, based on nitrogen atom to be quaternized, and at a temperature of from 40xc2x0 to 120xc2x0 C.